Germination profiling of lentil genotypes subjected to salinity stress

Abstract

Salinity is one of the most severe environmental stresses, negatively affecting productivity of salt-sensitive crop species. Given that germination is the most critical phase in the plant life cycle, the present study aimed to determine seed germination potential and associated traits under salt stress conditions as a simple approach to identify salt-tolerant lentil genotypes. The genetic material consisted of six lentil genotypes whose adaptation to various agroclimatic conditions is not well elucidated. Salinity stress was applied by addition of NaCl at three different levels of stress, while non-stressed plants were included as controls. Evaluation of tolerance was performed on the basis of germination percentage, seed water absorbance, root and shoot length, seedling water content, seedling vigour index and number of seedlings with an abnormal phenotype. Overall, our findings revealed that salinity stress substantially affects all traits associated with germination and early seedling growth, with the effect of salinity being dependent on the level of stress applied. It is noteworthy, however, that genotypes responded differently to the varying salinity levels. In this context, Samos proved the most salt-tolerant genotype, indicating its possible use for cultivation under stress conditions. In conclusion, the determination of seed germination and early growth potential may be exploited as an efficient strategy to reveal genetic variation in lentil germplasm of unknown tolerance to salinity stress. This approach allows selection of desirable genotypes at early growth stages, thus enabling more efficient application of various breeding methods to achieve stress-tolerant lentil genotypes. © 2018 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands